Device for producing stimulated infrared emission,iraser,by means of an electric discharge in a gas mixture consisting at least partly of carbonic acid and discharge tube for such a divice

ABSTRACT

An infrared laser employing a discharge in carbonic acid gas in a quartz tube, the electrodes consisting of platinum cylinders surrounding interruptions in the quartz tube.

United States Patent [72 Inventors Henricu Joann Franciscus Gerardus[52] U.S. Cl 331/945 Smets; [51] Int. Cl H015 3/02 Auke Gerrit Van DerKooi, o of 50] Field of Search 33 1 945; Emmasingel, Eindhoven,Netherlands 330 43 [2]] Appl. No. 799,384

[22] Filed Feb. 14, 1969 [56] References Cited 1 1 Patented p UNITEDSTATES PATENTS 73 Assignee gas-53:21:; s p 3,452,295 6/1969 Sher 331/945l 32 1 Priority Feb. 19, 1968 3,460,053 8/1969 Leonard 331/945 [33]Netherl d Primary Examiner-William L. Sikes [31] 6802368 Attorney-FrankR. Trifari [54] DEVICE FOR PRODUCING STIMULATED INFRARED EMISSION,IRASER, BY MEANS OF AN ELECTRIC DISCHARGE IN A GAS MIXTURE CONSISTING ATLEAST PARTLY OF CARBONIC ACID AND DISCHARGE TUBE FOR SUCH A DEVICE 5Claims, 2 Drawing Figs.

' ABSTRACT: An infrared laser employing a discharge in carbonic acid gasin a quartz tube, the electrodes consisting of platinum cylinderssurrounding interruptions in the quartz tube.

PATENIED SEP28 I971 uni" I 13 n 2 INVENTOR) HE NRICUS J.F.G. SMETS A BYUKE a v0 KOOI AGENT DEVICE FOR PRODUCING STIMULATED INFRARED EMISSION,IRASER, BY MEANS OF AN ELECTRIC DISCHARGE IN A GAS MIXTURE CONSISTING ATLEAST PARTLY OF CARBONIC ACID AND DISCHARGE TUBE FOR SUCII A DEVICE Theinvention relates to a device for producing stimulated infraredemission, an iraser, by means of an electric discharge in a gas mixtureconsisting at least partly of carbonic acid in a circular cylindricalquartz tube, the electrodes being arranged laterally of the iraserresonator.

In the device known from Dutch Patent application No. 6,509,730 theelectrodes are arranged in side tubes of the discharge space.

The discharge path in the resonator space therefore does not extendsymmetrically at the ends. This has an unfavorable influence on the modepattern and the irradiated power.

It is the object of the invention to provide a construction which avoidsthe above drawbacks.

According to the invention, a device is provided for producingstimulated infrared emission, an iraser, by means of an electricdischarge in a gas mixture consisting at least partly of carbonic acidin a circular cylindrical quartz tube. The electrodes are arrangedlaterally of the iraser resonator and consist of circular-cylindricalrings which are arranged coaxially with the discharge space on theoutside of the quartz tube. The rings surround a circumferentialinterruption in the quartz tube with wider quartz tubes surrounding theelectrodes and connecting the interrupted parts together in avacuumtight manner.

The interruption in this construction need be only narrow, less than 1mm. because the current intensity usually is less than 100 mm. At thetotal pressure of approximately Torr. the discharge current distributesregularly over the whole circumference of the interruptions so that thewhole cross section of the tube contributes evenly to the discharge anda favorable symmetrical mode pattern is obtained. As a result of thenarrow interruption, very little sputtering occurs inside the dischargespace.

In order that the invention may be readily carried into effect, oneembodiment thereof will now be described in greater detail, by way ofexample, with reference to the accompanying drawing, in which FIG. 1diagrammatically shows a discharge tube according to the invention, and

FIG. 2 shows a part thereof at a given stage of the manufacture on anenlarged scale.

Referring now to FIG. 1, reference numeral 1 denotes a quartz tube, 2.0m. long, mm. inside diameter. On the lefthand side the tube is sealed ina vacuumtight manner by means of a concave ground aluminum block 2(radius of curvature 4.5 m.) coated with a layer of gold 3.0. On theother side a flat germanium plate 4 (2 mm. thick) closes the tube.

The tube 1 is interrupted at 5 and 6 over a length of 0.5 mm.

the parts being connected by wider tubes 7 and 8. In the latter tubes,the platinum cylinders 10 are arranged at a distance of 0.5 mm. from thetube I and the elongations thereof. Tungsten lead-in members 11 and 12support the electrodes. The exhaust tube is denoted by 13.

FIG. 2 shows the right-hand part of the tube in a state in which it isnot yet entirely finished. The tube 8 is sealed on the left-hand side totube 1, the electrode 10 surrounds the copper cylinder 14, 0.5 mm.thick, which engages the tube The elongation 16 of tube 1 is inserted onthe right-hand side in the cylinder I4 until it engages the edge 15which, from the cylinder 14, is directed inwardly and is enclosedbetween the tubes 1 and 16. The electrode 10 is previously welded to thelead-in member 12. After inserting the elongation 16, the sealing edge17 may be formed. After dissolving the copper cylinder 14 in nitricacid, the tube may be finished.

What is claimed is:

I. A device for producing stimulated infrared emission comprising meansincluding electrodes for providing an electric discharge in a dischargespace containing a gas mixture consisting at least part] of carbonicacid in a circular-cylindrical quartz tube, said In e includingcircumferential interruptions,

the electrodes being arranged laterally of the discharge space, saidelectrodes having the shape of circular-cylindrical rings arrangedcoaxially with said discharge space on the outside of said quartz tubeand each surrounding a circumferential interruption, wider quartz tubessurrounding said electrodes and connecting the interrupted partstogether in a vacuumtight manner.

2. A discharge tube for a device as claimed in claim I wherein the widthof the interruption is a few tenths of a mm. and the electrodes surroundthe interruption with a distance of a few tenths of a mm. each of saidelectrodes being composed of platinum.

3. A device for producing stimulated infrared emission by means of anelectric discharge in gas mixture comprising a circular cylindricallyshaped quartz tube including first and second circumferentialinterruptions, first and second electrodes for providing said electricdischarge, said electrodes each positioned laterally with respect tosaid tube and shaped as circular cylindrical rings arranged coaxiallywith said tube and surrounding a respective one of said circumferentialinterruptions, and means surrounding said electrodes and interconnectingthe interrupted portions of said tube together in a vacuumtight manner.

4. The combination of claim 3 wherein each of said means surroundingsaid electrodes is a quartz tube.

5. A discharge tube for a device as claimed in claim 3, wherein thewidth of the interruption is a few tenths of a mm. and the electrodessurround the interruption with the distance of a few tenths of a mm.,each of said electrodes being composed of platinum.

2. A discharge tube for a device as claimed in claim 1 wherein the widthof the interruption is a few tenths of a mm. and the electrodes surroundthe interruption with a distance of a few tenths of a mm. each of saidelectrodes being composed of platinum.
 3. A device for producingstimulated infrared emission by means of an electric discharge in gasmixture comprising a circular cylindrically shaped quartz tube includingfirst and second circumferential interruptions, first and secondelectrodes for providing said electric discharge, said electrodes eachpositioned laterally with respect to said tube and shaped as circularcylindrical rings arranged coaxially with said tube and surrounding arespective one of said circumferential interruptions, and meanssurrounding said electrodes and interconnecting the interrupted portionsof said tube together in a vacuumtight manner.
 4. The combination ofclaim 3 wherein each of said means surrounding said electrodes is aquartz tube.
 5. A discharge tube for a device as claimed in claim 3,wherein the width of the interruption is a few tenths of a mm. and theelectrodes surround the interruption with the distance of a few tenthsof a mm., each of said electrodes being composed of platinum.